Lowering dietary fat is recommended. (For the sake of this discussion, "fat" is meant to be synonymous with both animal and vegetable fat and shortening.) In the preparation of baked goods fat lubricates and reduces viscosity of the dough, retards starch from swelling and from gelatinizing. It also provides flavor and tenderness to the final product. Methods for making low or fat-free (no added fat) baked goods must somehow compensate for the multiple functions of fat when reducing or eliminating fat.
Machinability is an important consideration in preparing crackers. U.S. Pat. No. 2,144,720 issued to Gibson on Jan. 24, 1939 for a complicated cracker device illustrates the obstacles dough will experience when being fashioned into a product. If a cracker dough is not machinable on a mass production basis, it loses its commercial utility. On a mass production basis, a cracker dough must be continuously sheetable, and in the case of fermented crackers it should also preferably be capable of being laminated upon itself. The baked product should be non-brittle so as to be transferrable between conveyer belts and packaging equipment without excessive breakage.
Water can be used to reduce viscosity and to provide adequate lubrication to the dough in the absence of fat but water cannot be used to provide tenderness to the final product. Fat-free crackers made only with water as the fat replacement are flinty and so absorptive as to cause unpleasant dryness in the mouth upon eating.
Japanese specification 61-293346, U.S. Pat. No. 3,982,032 Koizumi and U.S. Pat. No. 3,860,735 of Hoshino disclose rice crackers apparently made without fat or shortening. German specification 28 00 603 and Japanese specification 45 37830 disclose rye crackers and Japanese specification 45 37830 also discloses a cracker all apparently made without added fat or shortening. There are products which do not require fat in their preparation but the invention is not concerned with such things. The problem facing the inventors is how to replace fat in methods ordinarily requiring fat and still maintain a quality product while continuously producing it on a mass production scale.
There are many protocols for baked goods which require fat. Holmes describes the use of lard in his cream cracker in U.S. Pat. No. 58,644 issued in 1866. Johnson describes adding oil to his cracker while it is hot in the oven in U.S. Pat. No. 882,006 issued in 1908. Rippey describes using coconut oil in his cracker in U.S. Pat. No. 1,633,872 issued in 1927. The pharmaceutical wafers of Schneiderworth, designed for weight loss, have shortening as described in Canadian Patent 526,576 issued in 1956. Wolf describes a compressed cracker which has oil in U.S. Pat. No. 3,937,852 issued Feb. 10, 1976. The soda crackers of Sugihara have shortening as described in U.S. Pat. No. 4,353,926 issued Oct. 12, 1982. The low sodium crackers and cookies of Arciszewski et al. use shortening as described in European application 0286723 published Oct. 19, 1988. von Loesecke, Harry, W. Outlines of Food Technology, (Reinhold Publishing Company, New York, 1942) pp. 266-267 discloses formulas for biscuits and crackers requiring lard or shortening. Matz, Samuel A. Snack Food Technology, (The AVI Publishing Company, Inc., Westport, Conn. 1976). pp. 150-156 discusses the use of shortening and fat in soda crackers. Heppner, Walter A. "The fundamentals of Cracker Production", The Baker's Digest, April 1959, pp. 68-70 and 85-86, relates to a method for making a fermented cracker using fat.
Cooke et al. describe using pentosanase in a dough used to make bread in U.S. Pat. No. 3,512,992 issued May 19, 1970. In addition to pentosanase treatment, the method of Cooke et al. also requires shortening. Miyamoto uses amylase and protease in the manufacture of his crackers along with shortening as described in U.S. Pat. No. 3,281,249 issued Oct. 25, 1966. Fazzolare et al. describe using enzymes to relax gluten in the dough used to make crackers containing sunflower seeds as set out in U.S. Pat. No. 4,595,596 issued on Jun. 17, 1986 and as described in related U.S. Pat. No. 4,761,296 issued on Aug. 2, 1988. Fazzolare et al. also use shortening.
Gaines et al. "Effects of Selected Commercial Enzymes on Cookie Spread and Cookie Dough Consistency" Cereal Chemistry, vol. 66, no. 2, 1989, pp. 73-78, discloses the use of commercial-grade enzymes including cellulases in the production of cookies.
The relative effects on the viscosity of rye flour suspensions exhibited by various enzymes such as protease, pentosanase, and alpha-amylase is disclosed in Bruemmer, G. M. "Baking Components" Brot and Geback, vol. 25, No. 11, (November 1971), pp. 217,220 and in its Chemical Abstract no. 98049q, vol. 76, page 333 (1972). The use of .alpha.-amylase for liquefying starch is disclosed in European Patent Application 0 180 942 published May 14, 1986.
Simpson describes the use of pentosanase for the recovery of starch from gluten separations in U.S. Pat. No. 2,821,501 issued on Jan. 28, 1958. (Also, see Canadian Patent 603,953 issued Aug. 23, 1960.) Pentosanase has been used in the refining of starch as described in Japanese specification 57-141297 published Sep. 1, 1982. Pentosanase has been used to treat wastewaters from the wheat starch industry. (Wieg, A. J. "Enzymic treatment of wastewaters from the wheat starch industry" Starch/Staerke, Vol. 36, No. 4. (1984), pp. 135-140.)
The substrate for pentosanase in doughs is comprised of pentosans which are polysaccharides. Pentosans can comprise as much as 1-2% by weight of flour yet up to 23.4% of water distribution in dough can be associated with the pentosans. (Bushuk, W. "Distribution of Water in Dough and Bread", Baker's Digest, Vol. 40, No. 5, (October 1966), pp. 38-40.) Pentosans have been characterized as comprising two fractions, soluble and insoluble. (Medcalf et al. "Comparison of Chemical Composition and Properties between Hard Red Spring and Durum Wheat Endosperm Pentosans", North Dakota State University, Fargo, Journal Series No. 131, April 1967; Medcalf et al. "Structural Characterization of a Pentosan from the Water Insoluble Portion of Duram Wheat Endosperm" North Dakota State University, Fargo, Journal Series No. 130, November 1968.)
Microbial pentosanases are discussed in Simpson, F. J. "Microbial Pentosanases I. A Survey of Microorganisms for the Production of Enzymes that Attack the Pentosans of Wheat Flour", Canadian Journal of Microbiology, Vol. 1, No. 2, (October 1954), pp. 131-139. Measuring pentosanase activity is discussed in Fretzdorff, B. "Determination of .beta.-xylosidase activity in rye" Z. Lebenson Unters Forsch, Vol. 167, No. 6, (1978), pp. 414-418. Characterization of pentosanase as a hydrolytic enzyme produced in germinating barley occurs in Palmer et al. "Influence of Enzyme Distribution on Endosperm Breakdown (Modification during Malting", Journal of the American Society of Brewing Chemists, Vol. 43, No. 1, 1985, pp. 17-28. Fungal, thermostable pentosanases are discussed in U.K. Patent Application 2 150 933 published Jul. 10, 1985.
Casier describes using a preparation of pentosans as an additive to soften flours and enable bread making from rice flours and the like. (British Patent 1,332,903 issued published Oct. 10, 1973.) Casier found that by the addition of rye pentosans, bread volume would be increased and shelf life extended. Support for Casier is found in the article of Jankiewicz et al. "The Effect of Soluble Pentosans Isolated from Rye Grain on Staling of Bread", Food Chemistry, Vol. 25, (1987), pp. 241-249.
Pentosans comprise several fractions having different functional properties. Rendering insoluble pentosans soluble with enzymes improved the baking quality of the fraction to that of prime starch. (Kulp, K. "Enzymolysis of Pentosans of Wheat Flour", Cereal Chemistry, Volume 45, No. 4, (July, 1968), pp. 339-350.) Soluble pentosans have been reported to affect dough viscosity. (Drews, E. "Amylograms with respect to some quality criteria of rye and its mill products", Brot and Geback, Vol. 23, No. 9, (1969), pp. 165-170.)
Pentosanases have been reported to reduce viscosity, improve volume, lightness and crumb quality of both rye and wheat breads. (Botsch, A. "Possibilities for Utilization of New Enzymic Baking Additives", Brot and Geback, Vol. 23, No. 10, (1969), pp. 202-203.) Pentosanase activity has been reported to improve softness of bread and resistance to staling. (U.S. Pat. No. 3,512,992 issued to Cooke et al. on May 19, 1970.)
There are problems with using too much pentosanase which can reduce volume of bread where optimal amounts increase volume of bread. (Johansson et al. "Composition of Water-soluble Pentosans in Wheat Flour and Doughs and the Effect of Pentosanases on Kneading during Dough Development", Sveriges Utsadesforenings Tidskrift, Vol. 81, (1971), pp. 282-301.) A study of the effects of amylases, proteases, cellulases, pentosanases and pectinase on rye flour concluded that the pentosanases and proteases lowered dough viscosity the most. However, five fold increases in enzymes were no more effective than a single dose. (Weipert, D. "Rheology of Rye Dough", Getreide, Mehl Brot, Vol. 26, No. 10, (1972), pp. 275-280.)
Casier mentions the use of pentosanase as an adjuvant for promoting breadmaking in Brevet Canadian 927,826 issued Jun. 5, 1973. Krebs et al. discuss improvements in the crush of bread by pentosanase in Offenlegungsschrift 2,227,368 published Oct. 17, 1974. One report mentions that pentosanases do not affect viscosity of wheat starch hydrolysates. (Tegge et al. "Enzymic Hydrolysis of Various Starches", Starch/Staerke, Vol. 38, No. 10, (1986), pp. 329-335.)
Cracker making involves different problems from that of bread making. For example, in bread making gelation of starch and maintaining moisture in the bread are objectives. When bread goes stale it becomes hard. When crackers go stale they become soft. The inventors have found that in preparing crackers without the addition of fat, a machineable cracker dough using only water as the fat replacement provides a product with inferior texture.
A major source of the textural problem is believed to be excessive gelatinization of starch in the cracker made with extra water without adding fat. Indeed, the inventors have discovered that excessive gelatinization of starch during baking makes the cracker flinty and very moisture absorbent. Retention of water in the cracker dough during baking causes excessive gelatinization and the resultant inferior cracker. Thus, when preparing crackers, unlike preparing bread, starch gelatinization is to be minimized.
A wet preparation of flour type products from cereal grains without gelatinizing the starch is described in U.S. Pat. No. 4,435,429 issued to Burrows et al. on Mar. 6, 1984. Note that Burrows et al. are not concerned with minimizing gelatinization of starch in final products, rather the preparation of oat flour is the goal.
In the present invention, the added fat or shortening content of a mass produced cracker reduced using water and an enzyme composition. Dough machinability is retained and excessive starch gelatinization is avoided in the cracker even though the added fat level is substantially reduced or completely eliminated and water levels are increased on a flour basis. The enzyme composition is used to minimize starch gelatinization during baking by decreasing the amount of water used to form a machinable no-fat or reduced fat dough and by increasing the dough's ability to release water faster. Less water present during baking translates to less gelatinization of starch. The reduced fat or no-added fat crackers of the present invention exhibit a shelf-stable, tender, non-brittle texture over extended periods of time.